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Novel Door-opening Method for Six-legged Robots Based on Only Force Sensing

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1227-1238页

作者： Zhi-Jun Chen Feng Gao yang Pan State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai GQY Robot Limited Company

Current door-opening methods are mainly developed on tracked, wheeled and biped robots by applying multi-DOF manipulators and vision systems. However, door-opening methods for six-legged robots are seldom studied, especially using 0-DOF tools to operate and only force sensing to detect. A novel door-opening method for six-legged robots is developed and imple- mented to the six-parallel-legged robot. The kinematic model of the six-parallel-legged robot is established and the model of measuring the positional relationship between the robot and the door is proposed. The measurement model is completely based on only force sensing. The real- time trajectory planning method and the control strategy are designed. The trajectory planning method allows the maximum angle between the sagittal axis of the robot body and the normal line of the door plane to be 45°. A 0-DOF tool mounted to the robot body is applied to operate. By integrating with the body, the tool has 6 DOFs and enough workspace to operate. The loose grasp achieved by the tool helps release the inner force in the tool. Experiments are carried out to validate the method. The results show that the method is effective and robust in opening doors wider than 1 m. This paper proposes a novel door-opening method for six-legged robots, which notably uses a O-DOF tool and only force sensing to detect and open the door.

关键词： Door-opening·Six-legged robots· Forcesensing · O-DOF tool

Application of sparse S transform network with knowledge distillation in seismic attenuation delineation

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Petroleum Science 2024年第4期21卷 2345-2355页

作者： Nai-Hao Liu Yu-Xin Zhang yang yang Rong-Chang Liu Jing-Huai Gao Nan Zhang School of Information and Communications Engineering Xi'an Jiaotong UniversityXi'an710049ShaanxiChina School of Software Engineering Xi'an Jiaotong UniversityXi'an710049ShaanxiChina PetroChina Research Institute of Petroleum Exploration and Development(RIPED) CNPCBeijing100083China Research Institute of Exploration and Development Yumen Oilfield CompanyCNPCJiuquan735019GansuChina

Time-frequency analysis is a successfully used tool for analyzing the local features of seismic ***,it suffers from several inevitable limitations,such as the restricted time-frequency resolution,the difficulty in selecting parameters,and the low computational *** by deep learning,we suggest a deep learning-based workflow for seismic time-frequency *** sparse S transform network(SSTNet)is first built to map the relationship between synthetic traces and sparse S transform spectra,which can be easily pre-trained by using synthetic traces and training ***,we introduce knowledge distillation(KD)based transfer learning to re-train SSTNet by using a field data set without training labels,which is named the sparse S transform network with knowledge distillation(KD-SSTNet).In this way,we can effectively calculate the sparse time-frequency spectra of field data and avoid the use of field training *** test the availability of the suggested KD-SSTNet,we apply it to field data to estimate seismic attenuation for reservoir characterization and make detailed comparisons with the traditional time-frequency analysis methods.

关键词： S transform Deep learning Knowledge distillation Transfer learning Seismic attenuation delineation

Tailoring Optical and Plasmon Resonances in Core-shell and Core-multishell Nanowires for Visible Range Negative Refraction and Plasmonic Light Harvesting:A Review

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Journal of Materials Science & Technology 2015年第6期31卷 533-541页

作者： Sarath Ramadurgam Tzu-Ging Lin Chen yang Department of Physics and Astronomy Purdue University Department of Chemistry Purdue University

Semiconductor nanowires(NWs) are sub-wavelength structures which exhibit strong optical(Mie)resonances in the visible *** addition to such optical resonances,the localized surface plasmon resonances(LSPRs) in metal-semiconductor core-shell(CS) and core-multishell(CMS) NWs can be tailored to achieve novel negative-index metamaterials(N1M),extreme absorbers,invisibility cloaks and ***,in this review,we focus on our recent theoretical studies which highlight the versatility of CS and CMS NWs for:1) the design of negative-index metamaterials in the visible range and2) plasmonic light harvesting in ultrathin photocatalyst layers for water *** the LSPR in the metal layer and the magnetic dipole(Mie) resonance in the semiconductor shell under transverse electric(TE) polarization,semiconductor-metal-semiconductor CMS NWs can be designed to exhibit spectrally overlapping electric and magnetic resonances in the visible *** exhibiting such double resonances can be considered as meta-atoms and arrayed to form polarization dependent,low-loss ***,by tuning the LSPR in the TE polarization and the optical resonance in the transverse magnetic(TM) polarization of metal-photocatalyst CS and semiconductor-metal-photocatalyst CMS NWs,the absorption within ultrathin(sub-50 nm) photocatalyst layers can be substantially ***,aluminum and copper based NWs provide absorption enhancement remarkably close to silver and gold based NWs,***,such absorption is polarization independent and remains high over a large range of incidence angles and permittivity of the ***,due to the tunability of their optical properties,CS and CMS NWs are expected to be vital components for the design of nanophotonic devices.

关键词： Nanowires Core-shell Core-multishell Negative refr

Calibration of Gridded Wind Speed Forecasts Based on Deep Learning

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Journal of Meteorological Research 2023年第6期37卷 757-774页

作者： Xuan yang Kan DAI Yuejian ZHU National Meteorological Centre Beijing100081China NOAA/NWS/NCEP/Environmental Modeling Center College ParkMaryland20740USA

The challenges of applying deep learning(DL) to correct deterministic numerical weather prediction(NWP) biases with non-Gaussian distributions are discussed in this *** is known that the DL UNet model is incapable of correcting the bias of strong winds with the traditional loss functions such as the MSE(mean square error),MAE(mean absolute error),and WMAE(weighted mean absolute error).To solve this,a new loss function embedded with a physical constraint called MAE_MR(miss ratio) is *** performance of the UNet model with MAE_MR is compared to UNet traditional loss functions,and statistical post-processing methods like Kalman filter(KF) and the machine learning methods like random forest(RF) in correcting wind speed biases in gridded forecasts from the ECMWF high-resolution model(HRES) in East China for lead times of 1–7 *** addition to MAE for full wind speed,wind force scales based on the Beaufort scale are derived and *** to raw HRES winds,the MAE of winds corrected by UNet(MAE_MR) improves by 22.8% on average at 24–168 h,while UNet(MAE),UNet(WMAE),UNet(MSE),RF,and KF improve by 18.9%,18.9%,17.9%,13.8%,and 4.3%,*** with MSE,MAE,and WMAE shows good correction for wind forces 1–3 and 4,but negative correction for 6 or ***(MAE_MR) overcomes this,improving accuracy for forces 1–3,4,5,and 6 or higher by 11.7%,16.9%,11.6%,and 6.4% over HRES.A case study of a strong wind event further shows UNet(MAE_MR) outperforms traditional post-processing in correcting strong wind biases.

关键词： deep learning wind speed grid forecasting loss function statistical post-processing

New two-layer Ruddlesden-Popper cathode materials for protonic ceramics fuel cells

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Journal of Advanced Ceramics 2021年第5期10卷 1052-1060页

作者： Yihan LING Tianming GUO yangyang GUO yang yang Yunfeng TIAN Xinxin WANG Xuemei OU Peizhong FENG School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China

New two-layer Ruddlesden-Popper(RP)oxide La_(0.25)Sr_(2.75)FeNiO_(7-δ)(LSFN)in the combination of Sr_(3)Fe_(2)O_(7-δ) and La_(3)Ni_(2)O_(7-δ) was successfully synthesized and studied as the potential active single-phase and composite cathode for protonic ceramics fuel cells(PCFCs).LSFN with the tetragonal symmetrical structure(IMmmm)is confinned,and the co-existence of Fe^(3+)/Fe^(4+) and Ni^(3+)/Ni^(2+) couples is demonstrated by X-ray photoelectron spectrometer(XPS)*** LSFN conductivity is apparently enhanced after Ni doping in Fe-site,and nearly three times those of Sr_(3)Fe_(2)O_(7-δ),which is directly related to the carrier concentration and conductor ***,anode supported PCFCs using LSFN-BaZr_(0.1)Ce_(0.7)Y_(0.2)O_(3-δ)(LSFN-BZCY)composite cathode achieved high power density(426 mW·cm^(-2) at 650℃)and low electrode interface polarization resistance(0.26Ω·cm^(2)).Besides,distribution of relaxation time(DRT)function technology was further used to analyse the electrode polarization *** observed three peaks(Pl,P2,and P3)separated by DRT shifted to the high frequency region with the decreasing temperature,suggesting that the charge transfer at the electrode-electrolyte interfaces becomes more difficult at reduced *** results demonstrate that new two-layer RP phase LSFN can be a promising cathode candidate for PCFCs.

关键词： protonic ceramics fuel cells(PCFCs) Ruddlesden-Popper(RP)phase single-phase cathode distribution of relaxation time(DRT)function charge transfer

Development status of novel spectral imaging techniques and application to traditional Chinese medicine

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Journal of Pharmaceutical Analysis 2023年第11期13卷 1269-1280页

作者： Qi Wang Yong Zhang Baofeng yang Department of Medicinal Chemistry and Natural Medicinal Chemistry College of PharmacyHarbin Medical UniversityHarbin150081China Department of Pharmacology(The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China Key Laboratory of Cardiovascular ResearchMinistry of Education)College of PharmacyHarbin Medical UniversityHarbin150081China Research Unit of Noninfectious Chronic Diseases in Frigid Zone Chinese Academy of Medical SciencesHarbin150081China Institute of Metabolic Disease Heilongjiang Academy of Medical ScienceHarbin150086China Department of Pharmacology and Therapeutics Melbourne School of Biomedical SciencesFaculty of MedicineDentistry and Health Sciences University of MelbourneMelbourneVIC3010Australia

Traditional Chinese medicine(TCM)is a treasure of the Chinese nation,providing effective solutions to current medical *** spectral techniques are undergoing continuous development and provide new and reliable means for evaluating the efficacy and quality of *** spectral techniques are noninvasive,convenient,and sensitive,they have been widely applied to in vitro and in vivo TCM evaluation *** this paper,previous achievements and current progress in the research on spectral technologies(including fluorescence spectroscopy,photoacoustic imaging,infrared thermal imaging,laser-induced breakdown spectroscopy,hyperspectral imaging,and surface enhanced Raman spectroscopy)are *** advantages and disadvantages of each technology are also ***,the future applications of spectral imaging to identify the origins,components,and pesticide residues of TCM in vitro are ***,the evaluation of the efficacy of TCM in vivo is *** future applications of spectral imaging is anticipated to promote medical research as well as scientific and technological explorations.

关键词： Chinese medicine Spectral imaging Fluorescence spectroscopy Photoacoustic imaging

Solution-Processed Silver Nanowire as Flexible Transparent Electrodes in Organic Solar Cells

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Chinese Journal of Chemistry 2021年第8期39卷 2315-2329页

作者： Yi yang Bowei Xu Jianhui Hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Organic solar cells(OSCs)have attracted much attention due to their advantages in fabricating flexible and semi-transparent ***,the light weight,flexibility and spectral adjustability make OSCs superior to silicon,perovskite and other thin film based solar cells in applications of integrated photovoltaic devices and wearable *** flexible and semi-transparent OSCs,transparent conducting electrodes(TCEs)play a key role in obtaining high *** various TCEs,silver1 n anowire(AgNW)has become a promisi ng can didate due to its low sheet resistance,high optical transparency,excellent mechanical flexibility and solution *** this article,we review the recent advances in AgNW-based TCEs and their applications in the field of ***,we introduce the general properties of AgNW including optoelectronic and mechanical ***,the preparation methods of AgNW are discussed,along with some approaches on the optimization of AgNW to overcome the shortcomings of ***,we discuss the applications of AgNW as TCEs in fabricating flexible and semi-transparent OSCs,including the use of AgNW as bottom and top ***,we point out the challenges in AgNW-based TCEs and suggest several guidelines for preparing AgNW so as to meet the demands for the practical use of OSCs.

关键词： Silver Nanostructures Conducting materials Electrode Organic solar cells

Investigating the co-evolution of massive black holes in dual active galactic nuclei and their host galaxies via galaxy merger simulations

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Science China(Physics,Mechanics & Astronomy) 2019年第12期62卷 96-109页

作者： Chao yang JunQiang Ge You Jun Lu National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory for Computational Astrophysics National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China

Major galaxy mergers can trigger nuclear activities and are responsible for high-luminosity quasi-stellar objects/active galactic nuclei(QSOs/AGNs). In certain circumstances, such mergers may cause dual active galactic nuclei(dAGN) phenomenon. This study investigates dAGN triggering and evolution of massive black holes(MBHs) during the merging processes using hydrodynamic code GADGET-2 to simulate several gas-rich major mergers at redshift z = 2 and 3, respectively. Results reveal that gas-rich major mergers can trigger significant nuclear activities after the second and third pericentric passages and the formation of dAGN with significant time duration(~10-390 Myr). During the merging processes, galactic bulge evolves with time because of the rapid star formation in each(or both) galactic centers and initial mixing of stars in galactic disks due to violent *** grow substantially due to accretion and finally merge into a bigger black hole. The growth of galactic bulges and corresponding increases of its velocity dispersions predate the growth of MBHs in the d AGN stages. The MBHs in these stages deviate below the relation between MBH mass and bulge mass(or velocity dispersion), and they revert to the relation after the final mergers due to the significant accretion that occurs mostly at a separation less than a few kpc. Then, the two MBHs merge with each other.

关键词： galaxies quasars black hole numerical simulations

Facile Synthesis of Functional Poly (ε-caprolactone) via Janus Polymerization

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Chinese Journal of Polymer Science 2019年第9期37卷 858-865页

作者： Huan Qiu Zhe-Ning yang Jun Ling Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

Functionalized aliphatic polyesters attract increasing attentions as biocompatible and biodegradable polymers with broad applications in biological science. In this contribution, we propose a facile and controllable synthetic technique for functional poly(ε-caprolactone)(PCL) via Janus polymerization, which comprises cationic ring-opening copolymerization (ROP) of ε-caprolactone (CL) with 3,3-bis(chloromethyl)oxacyclobutane (CO) and (coordinated) anionic ROP of CL at a single propagating chain by rare earth metal triflates (RE(OTf)3)and propylene oxide, thus generating block copolymers in one step. The compositions of the copolymers of poly(CLb-(CL-r-CO)) can be modulated by various RE(OTf)3. Scandium triflate catalyzes Janus polymerization to yield the copolymers containing the highest CO contents among all the RE(OTf)3 catalysts used with complete conversion of CL. The chlorine in CO repeating units is ready to be transferred into azide group which affords the modification sites to react with 9-ethynyl-9-fluorenol and mPEG-alkyne, respectively, via copper(I)-catalyzed azide-alkyne cycloaddition reaction with quantitative conversions of azides, as confirmed by FTIR analyses. According to NMR and SEC analyses, copolymers (PCC-g-PEG) bearing a homo-PCL block and a PEG-grafted block of poly(CO-co-CL) demonstrate well-defined chemical structures. The investigations on thermal properties reveal the strong phase separation between PCL and PEG blocks. The amphiphilic PCC-g-PEG is able to sei住assemble into micelles in aqueous solution while cylindrical and lamellar morphologies are observed in bulk. We provide an efficient protocol to synthesize functional PCL combining onestep Janus polymerization and precise post-polymerization click reaction.

关键词： Janus polymerization Functional poly(ε-caprolactone) Poly(3,3-bis(chloromethyl)oxacyclobutane) Ring-opening polymerization Rare earth metal catalysts